Commutator-brush holder.



N0. 781,650. PATENTED FEB. 7, 1905. W. HEAP & W. A. BARNES.

GOMMUTATOR BRUSH HOLDER.

PPPPPP ATION FILED AUG. 15, 1904.

UNITED STATES Patented February '7, 1905.

PATENT OFFICE.

WILLIAM HEAP AND IVILLIAM ALFRED BARNES, OF BOLTON-LE-MOORS,

' ENGLAND.

COMMUTATOR-BRUSH HOLDER.

SPECIFICATION forming part of Letters Patent No. 781,650, dated February 7, 1905.

Application filed August 15,1904. Serial No. 220,727.

To all whom it may concern.-

Be it known that we, WILLIAM HEAP and \VILLIAM ALFRED BARNES, subjects of the King of Great Britain and Ireland, and residents of Horwich, Bolton-le-Moors, England, have in vented certain new and useful Improvements in ()ommutator-Brush Holders,of which the following is a specification.

This invention has for its object to provide a brush-holder for dynamos and the like which shall possess a minimum of parts and be extremely simple of construction, yet provide for all the necessary adjustments and conditions for the effective use of the holder.

Upon the accompanying drawings, Figure 1 illustrates a right-hand side elevation, and Fig. 2 a plan, of the improved holder. 3 illustrates a left-hand longitudinal section, and Fig. 4 an end view.

According to the invention the holder comprises two arms or cheeks a, of thin metal, joined by a floor part b. At their wider ends the arms are bored to loosely fit the brush-spindle cl. Between the arms and surrounding the spindle (Z, also fixed thereto by a taper pin 0, is a sleeve f, and in one with such sleeve is a segmental ratchet-Wheel 9. Also between the arms a and loosely fitting the reduced ends of the sleeve f are two leverarms it. Pivotall y mounted between the arms /z is a pawl Pivotally mounted between the checks (1, is a lever j, and between such lever and a lever-like extension of the pawl '1: is a spiral spring 70. The lever f has a short arm y' and such arm pokes through a slot Z in a plate on, slidably supported upon the floor part b. This plate at its forward end is of hook formation, and upon the under face of the floor part b is a ridge or projection b Between and by this latter and the hooked end of the plate at the carbon block or brush 0 is held, the rear part of the block and the space between the gripping parts being of dovetail shape, as shown, to insure the secure attachment of the block. With the block 0 in contact with the commutator a and the pawl '23 engaging the ratchet-segment g the spring 70 is in compression. Hence by tending to separate the lever jand pawl i it serves both to put a pressure on the brush and, through the small arm of the lever j, to put a tension on the plate on, and thus maintain a grip on the block. By altering the position of the pawl '11 relatively to the ratchet-segment g the pressure of the brush on the commutator is correspondingly increased or decreased, while by allowing the pawl to engage, say, the last few teeth the holder is free to rise to the potion shown in Fig. 3, the friction of the pawl with the teeth of the ratchet-segment being sufiicient to sustain it in the elevated position. Upon the arms 71 are projections it which when the tension is taken off the brush come against the holder and raise it, (see Fig. 3,) the tension on the brush or the range of movements being comparatively slight. To keep the plate on to its work, it passes below a crosspin 19 and below the boss of the lever In view of the radial adjustments the lever j and the extension of the pawl are formed with small cup-like perforations q, into which the ends of the spring is fit and to one or both of which the spring is permanently secured, so as to prevent its accidental dislodgment.

It will now be seen that we get a holder which affords a variable pressure to the brush, which enables all the adjustments to be ef fected by hand, enables the carbon to be readily renewed, and is composed of very few parts for the various adjustments.

What we claim is- A brush-holder comprising two metal and tapering arms with holes to fit the holder-spindle, and a fioor part joining such arms, a plate slidably fitted between the said arms and against the said fioor part and the end of the plate and the floor part so formed as to produce a vise for holding the brush, a spindle on which the said arms are mounted, a sleeve part also fitting the spindle and lying between the two arms of the holder, a segmental ratchet-wheel secured to the sleeve part, apair of arms loosely mounted on the ends of the said sleeve part, a pawl carried by the lastnamed arms, and said pawl forn'ied with a le- In witness whereof we havehereunto set our VOY-hkQ extension, :1 double-armed lever pivhands in the presence of two witnesses.

ind with one 11'11'1 en 'zi in the aforesaid slidr "7 h 7 WILLIAM ALFRED BAltNltb. 5 mg plate, and the other arm lying dn'eeth opposite the lever-like extension on the pawl, \Vmnesses: V

and a spiral spring lying between the said ex- .PIOKLES D. BAILEY,

tension and lever-arm, as set forth. JOHN CAMP. 

